Financially it's usually an expenditure; as it's not a (depreciable) capital asset for the vast majority of people.Money used for sailboats is not an investment.
It's an expenditure.
So is college. So is a trip to a lovely place, or a piece of art, all of which are significant costs and have benefits beyond the immediate.
The investment in your serenity, quality of life and enjoyment is not something you can calculate an ROI on in any manner according to GAAP. Do people continue to invest in their happiness and expend resources to improve their quality of life?